47 lines
1.4 KiB
JavaScript
47 lines
1.4 KiB
JavaScript
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function newEventHandler() {
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let thisObject = {
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name: undefined, // This is for debugging purposes only.
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listenToEvent: listenToEvent,
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stopListening: stopListening,
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raiseEvent: raiseEvent,
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finalize: finalize
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}
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let eventHandlers = [] // Here we store all the functions we will call when an event is raised.
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return thisObject
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function finalize() {
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eventHandlers = []
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}
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function listenToEvent(eventType, handler, extraData) {
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let eventSubscriptionId = newUniqueId()
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eventHandlers.push([eventType, handler, extraData, eventSubscriptionId])
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return eventSubscriptionId
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}
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function stopListening(pEventSubscriptionId) {
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for (let i = 0; i < eventHandlers.length; i++) {
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if (pEventSubscriptionId === eventHandlers[i][3]) {
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eventHandlers.splice(i, 1)
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return
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}
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}
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}
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function raiseEvent(eventType, event) {
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for (var i = 0; i < eventHandlers.length; i++) {
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/* We will execute all the functions listening to this event type. */
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if (eventHandlers[i][0] === eventType) {
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let handler = eventHandlers[i][1]
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let extraData = eventHandlers[i][2]
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handler(event, extraData)
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}
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}
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}
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}
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